"Ligand-Free" CuI-Catalyzed Highly Efficient Intramolecular S-Vinylation of Thiols with Vinyl Chlorides and Bromides
Qiwu Zhao, Ling Li, Yewen Fang, Deqian Sun and Chaozhong Li*
*Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032, People's Republic of China, Email: cligmail.sioc.ac.cn
Q. Zhao, L. Li, Y. Fang, D. Sun, C. Li, J. Org. Chem., 2009, 74, 459-462.
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With CuI as the catalyst and K3PO4 • 3 H2O as the base, a highly efficient, ligand-free intramolecular S-vinylation of thiols with vinyl chlorides or bromides was successfully implemented. Moreover, competition experiments revealed that the 4-exo cyclization is fundamentally preferred over other modes (5-exo, 6-exo, and 6-endo) of cyclization.
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Preference of 4-exo Ring Closure in Copper-Catalyzed Intramolecular Coupling of Vinyl Bromides with Alcohols
Y. Fang, C. Li, J. Am. Chem. Soc., 2007, 129, 8092-8093.